帕西乍罗样病毒对基孔肯雅病毒的复制传播抑制作用研究

Chikungunya fever is an Aedes-transmitted acute infectious disease induced by chikungunya virus (CHIKV). Recently, CHIKV has spread globally and caused a large numbers of epidemics, resulting in serious public health problems and economic lost. However, there are no available effective drugs and specific vaccines for CHIKV currently. Therefore, development of precise and environmental bio-control approaches has became a new hot topic in the field of arbovirus prevention and control. Phasi Charoen-like virus (PCLV) is a newly discovered insect-specific virus. We have found that those Aedes aegypti carrying PCLV were not susceptible to be infected by CHIKV compared with the negative control, suggesting that PCLV might inhibit the replication and transmission of CHIKV. To test this hypothesis, this project will artificially synthesize the genome of PCLV and rescue recombinant PCLV virus at first, then feed Aedes aegypti (the Rockefeller strain) mosquitoes with CHIKV through oral infection following intrathoracic injection with PCLV, which is in order to confirm the inhibition of the transmission of CHIKV by PCLV. Furthermore, the related inhibition mechanism will be explored at the cellular and mosquito level. Finally, we will collect a large number of wild-caught Aedes aegypti from Yunnan, Hainan and Guangdong provinces to assess the prevalence of PCLV and its association with CHIKV infection. The results of this project not only enhance our understanding on the functions of PCLV, but also provide new strategies for CHIKV prevention and control, fitting well to the national requirement on acute infectious diseases.

基孔肯亚热是由基孔肯亚病毒（CHIKV）经伊蚊叮咬传播引起的急性传染性疾病，近年来在全球大规模流行，给人们健康和社会经济带来严重负担，但目前仍无有效药物和疫苗上市。因此，开发精准且环保的生物防治措施已成为虫媒病毒防控领域新热点。帕西乍罗样病毒（PCLV）是新发现的一种昆虫特异性病毒，申请人前期研究发现感染PCLV的埃及伊蚊不易感染CHIKV，提示PCLV可能对CHIKV的复制传播有抑制作用。本项目拟先人工包装PCLV重组病毒，显微注射感染埃及伊蚊（洛克菲勒株），再给蚊虫经口感染CHIKV，验证PCLV对CHIKV的传播阻断作用；然后在蚊虫和细胞水平探索PCLV对CHIKV的复制抑制作用机制；最后在野生伊蚊水平评估PCLV的携带率及其与CHIKV感染的相关性。研究成果不仅可以丰富人们对PCLV的功能认识，而且还为开发新的CHIKV防控策略提供思路，符合国家对重大传染病防控的战略需求。

基孔肯雅热是由基孔肯雅病毒（chikungunya virus, CHIKV）引起的急性传染性疾病，主要由伊蚊叮咬传播，目前仍无有效药物和疫苗上市，因此开发精准环保的生物防治措施和寻找特异潜在的药物靶点迫在眉睫。昆虫特异性病毒只感染昆虫而无法在脊椎动物体内或相关细胞内复制，是理想的虫媒生物防治工具。本研究成功分离出纯化的细胞融合剂病毒(cell fusing agent virus, CFAV)，发现无论共感染还是间隔感染，CFAV都可以显著促进CHIKV的复制和释放，转录组学结果提示CFAV感染介导的细胞内吞和内质网蛋白质加工上调以及溶酶体下调有助于促进CHIKV的复制和组装。另外，单股正链 RNA 病毒复制复合物（replication complex，RC）的形成依赖于钙蛋白酶（calpain-2，CAPN2） 蛋白的活性。本研究发现CAPN活性抑制剂不仅可以抑制CHIKV的复制，还可抑制CHIKV感染引起的波形蛋白重排，提示波形蛋白的分布对CHIKV的复制具有重要意义。这些结果为CHIKV的生物防控和临床治疗提供了新的研发靶点。